This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

A remarkably well preserved tower dating all the way back to the Iron Age.

This picturesque archeological site looks like it was pulled straight from a fantasy novel.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

The oldest hall in Iceland was written of in the Sagas and features a centuries-old escape tunnel.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

A luxury hotel housed in a former 15th century Gothic church.

A beautiful maze marks where three countries meet.

This noble mash-up in eastern Luxembourg is part Medieval, part Renaissance, all castle.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

Visit the ancient, mysterious Roman catacombs ... in the Netherlands.

Built to house a chapter of the Knights Templar, this grandiose building is a relic of Freemasonry in Chicago a century ago.

A huge Megalithic chamber tomb located behind a cafe.

A chapel on a volcanic core, marking the end of a successful journey.

Learn about Iceland's hidden folk at this school dedicated to the study of elves.

This historic stone bridge has an entire neighborhood clinging to its sides.

This wooden hotel is a temple to German sustainability and forest conservation.

The small alleys in Lübeck's Old Town are a result of medieval urban sprawl.

One of the oldest masonic museums in Paris.

A museum of magic with a Sadist past.

The oldest stone house in Paris was built by its most famous alchemist.

The most visited, and possibly most controversial, museum in Germany.